Aiming device correcting for the inclined position of the wheels or platform



April 29 1924.

O. GRAUHEDING AIMING DEVICE CORRECTING FOR THE INCLINED POSITION OF THE WHEELS OR PLATFORM Filed Sept. 2, 1921 2 Sheets-Sheet 1 BY A'rromvsy M I: t

April 29, 1924. 1

O. GRAUHEDING AIMING DEVICE CORRECTING FOR THE INGLINED POSITION OF THE WHEELS OR PLATFORM Filed Sept. 2, 1921 2 Sheets-Sheet 2 INVENTOR aw BY ATTORNEYJ' Patented Apr. 29, 1924.

N l T ED ST OSKAR GRAUHEDING, 0F DUSSELDORF,

GERMANY, ASSIGNOR TO THE FIR-M 01f BHEINISCHE METALLWAAREN- "UN'D MASCHINENFABEIK, OF DUSSELDOBF- DERENDORIE, GERMANY.

.Q-IMING DEVICE CORRECTING FOR THE INCLINED POSITION OF THE WHEELS 0'3;

PLATFORM.

Application filed September 2, 1921. Serial No. 498,160.

To all whom it may concern:

Be it known that I, OSKAR GRAUHEDING, engineer, a citizen of Germany, residing at Dusseldorf, Germany, 28 Fischerstrasse, have invented certain new and useful Improvements in Aiming Device Correcting for the Inclined Position of the Wheels or Platform, of which the following is a specification.

The sights of guns are usually arranged laterally to the centre line of the barrel, and for that reason are also positioned laterally of the pivot-centre of the horizontal slide of the tangent sight. From this follows an error when aiming at auxiliary aiming ob jects in close proximity, since the gun sight will deviate laterally when turning it according to the horizontal adjustment.

In the accompanying drawings Fig. 1 illustrates this fact diagrammatically and Fig. 2 is a detail,

Fig. 3 a side elevation,

Fig. 4 a rear view, and

Fig. 5 a perspective view.

It is supposed in Fig. 1 that the gun is trained by means of an auxiliary aim Z which is in close proximity to the gun, per haps in a distance of one metre. If the angle or is the one ordered to'be given to the un for horizontal adjustment, the gun sight in the first place is swung in a direction opposite to the correct one of the gun by the value of the angle 0:. vThen the horizontal adjustment of the barrel is effected from the position shown on the drawings in full lines, until the line of sight again covers the auxiliary aim Z As may be seen from Fig. 1, in consequence, of the lateral position of the aiming device a parallel shifting of the line of sight by the amount :0 will occur. As soon as the barrel of the gun is turned by the angle a, the aiming device would be directed to the point Z but not to the auxiliary aim Z But as really the auxiliary aim Z was pointed at, an error occurs, so that-if the line of sight after turning travels through the auxiliary aim Z, the gun in fact has been swung round only by the angle a{5. Thus the gun did receive a wrong direction. I

It is evident that such error is the smaller, the greater the distance of the auxiliary aim from the gun. With distances of more than metres the error is practically of no con sequence, but it is, articularly in the case of guns for short distance fighting not always possible to aim at far distant objects used as auxiliary aims. Thus the error will in many cases cause trouble.

Now the present invention relates to an arrangement by which this error is avoided even in consideration of an inclined position of the wheels or platform. For thus purpose in the first place the gun sight is disposed in the centre of the pivot of the lateral adjusting device, in the second place the centre point of the graduation sector on which the telescope is adjusted, is shifted to the centre line of the trunnions,'so that the turning centre of the training circle always remains above the turning centre of the gun, during the vertical adjustment of the tangent sight and gun. In-case the difference caused by the inclined position of the wheels is to be corrected, then according to the invention on the third place, this is not be effected about any optional axis parallel to that of the bore of gun, but about the axis of the bore of the gun proper in order to prevent the gun sight from deviation even when correcting the difference of the inclined position of the wheel. According to Fig. 2 the inclination of the platform is Y and in consequence the gun sight must be turned by this angle 7 in order to maintain it vertically, and it can only return to its former position, if the turning axis coincides with the axis of the bore g y.

Therefore it is important, that during the three manipulations (1) Horizontal pointing of the gun,

(2)' Vertical pointing of the gun, and

(3) Obviating the diiference caused by the inclined position of the platform (inclination of the trunnions), the pointing circle of the gun sight does not deviate in relation to the auxiliary aim close by. These three conditions must be fulfilled in order to obtain an exact aiming device.

One mode of construction according to the invention is shown in Figs. 3, 4 and 5.

The support A is attached to the gun dismountably, and carries on its top the worm driver a, for correcting the diflerence of the inclined position of the wheels. A sector B having a guide I), provided for the support, disposed vertically to the axis of the bore of the gun, and whose radius is r, and Whose centre point is situated in the axis of the bore of the gun. The sector member B may be placed vertically by turning a driver at, and aided by a water level 0 by which operation the inclined posit-ion of the platform is equalized. Since the centre point of the sector guide is situated in the axis 3 of the bore, the telescope D together with the pointing circle al is returned to its for mer position. In the event of this centre point not being situated in the axis yy of the bore, vertical adjustment of the telescope is likewise possible, however the telescope will not return to its former position. Provided for instance the radius be one half 0, a parallel deviation of the pointing circle and consequently of the line of si ht would take place, corresponding to the ength of arc and half the value of the angle a. The graduation sector B which carries and guides the scale the tangent sight member 0 may be vertically adjusted by the gear (2 of the tangent sight. By this adjustment the water-level 0 will be inclined and then the wheel I for horizontal pointing be turned until the water level is indicating the desired incline. The centre point of this graduation arc with its radius 1' is situated in the centre W of the trunnion. This is attained in such a manner that the pointing circle d of the the gun with its axis an? resumes its former position again even with vertical adjustment of the tangent sight. According to the example shown the axis ww of the trunnion crosses the axis .22. This however is not a condition, since the trunnion may be positioned outside of these axes. But then attention must be paid to the radius 03 terminating in the centre point of the trunnion, and that the axis mm of the pointing circle is arranged above the axis 22 of the horizontal pointing device of the gun.

I claim:

1. In an aiming device for correcting the difference caused by the inclined position of the wheels or platform adapted for indirect pointing at an auxiliary aim in close'proximity, the combination of a gun having trunnions, a pointing circle having the axis thereof located above the turning axis of the gun in obtaining the horizontal adjustment of the gun, and a tangent sight having the arc of the radius thereof positioned in the center of the gun trunnions, said tangent sight being provided with an axis for cor recting the inclination of the trunnions with the axis of the bore of the gun.

2. In an aiming device for correcting the difierence caused by the inclined position of the wheels or platform adapted for indirect pointing at an auxiliary aim in close proximity the combination of a un having trunnions, a pointing circle having the axis thereof located above the turning axis of the gun in obtaining the horizontal adjustment of the gun, a tangent sight having the arc of the radius thereof positioned in the center of the gun trunnions, said tangent sight being provided with an axis for correcting the inclination of the trunnions with the axis of the bore of the gun, a turning axis of the pointing circle, the axis of the horizontal adjustment of the gun, the axis of the bore of the gun and the axis of the trunnion crossing one another at the same point.

In testimony whereof I have aifixed my signature in presence of two witnesses.

OSKAR GRAUHEDING.

Witnesses:

D. BrssEL, JOHANNES ScHxoEDER. 

